The present invention relates to a gas sensor, in particular a gas sensor having a sensor protection device for use in internal combustion engines.
Oxygen gas sensors are normally located after the combustion process in the exhaust flow of an internal combustion engine. In this location, the oxygen gas sensor is exposed mostly to hot exhaust gases. Oxygen gas sensors located before the combustion process, for example in the intake manifold, are exposed to cooler air that may have contaminants such as water, oil, fuel vapor, soot, particles, and other contaminants. These contaminants can cause damage to the oxygen gas sensor including thermal shock cracks, poisoning of the sensor element, and clogging of passage ways, among other things.